Related Experiment Video
Updated: Apr 7, 2026
A Novel Approach to Assess Motor Outcome of Deep Brain Stimulation Effects in the Hemiparkinsonian Rat: Staircase and Cylinder Test
Published on: May 31, 2016
Effects of subthalamic nucleus stimulation on motor cortex plasticity in Parkinson disease
Sang Jin Kim1, Kaviraja Udupa1, Zhen Ni1
1From the Division of Neurology (S.J.K., K.U., Z.N., E.M., C.G., F.M., A.E.L., R.C.), University of Toronto, Toronto Western Research Institute, University Health Network and the Edmond J. Safra Program in Parkinson's Disease, Toronto; Division of Neurosurgery and Toronto Western Research Institute (A.M.L., M.H.), University Health Network, University of Toronto; Brain & Spinal Cord Rehab Program (F.M.), Toronto Rehab, University Health Network, Canada; Service de Neurologie (E.M.), CHU Grenoble, Joseph Fourier University, Grenoble, France; and Department of Neurology (S.J.K.), Inje University College of Medicine, Busan, South Korea.
Objective:
We hypothesized that subthalamic nucleus (STN) deep brain stimulation (DBS) will improve long-term potentiation (LTP)-like plasticity in motor cortex in Parkinson disease (PD).
Methods:
We studied 8 patients with PD treated with STN-DBS and 9 age-matched healthy controls. Patients with PD were studied in 4 sessions in medication (Med) OFF/stimulator (Stim) OFF, Med-OFF/Stim-ON, Med-ON/Stim-OFF, and Med-ON/Stim-ON states in random order. Motor evoked potential amplitude and cortical silent period duration were measured at baseline before paired associated stimulation (PAS) and at 3 different time intervals (T0, T30, T60) up to 60 minutes after PAS in the abductor pollicis brevis and abductor digiti minimi muscles.
Results:
Motor evoked potential size significantly increased after PAS in controls (+67.7% of baseline at T30) and in patients in the Med-ON/Stim-ON condition (+55.8% of baseline at T30), but not in patients in the Med-OFF/Stim-OFF (-0.4% of baseline at T30), Med-OFF/Stim-ON (+10.3% of baseline at T30), and Med-ON/Stim-OFF conditions (+17.3% of baseline at T30). Cortical silent period duration increased after PAS in controls but not in patients in all test conditions.
Conclusions:
Our findings suggest that STN-DBS together with dopaminergic medications restore LTP-like plasticity in motor cortex in PD. Restoration of cortical plasticity may be one of the mechanisms of how STN-DBS produces clinical benefit.
